/**
  ******************************************************************************
  * @file    stm32g4xx_hal_exti.c
  * @author  MCD Application Team
  * @brief   EXTI HAL module driver.
  *          This file provides firmware functions to manage the following
  *          functionalities of the Extended Interrupts and events controller (EXTI) peripheral:
  *          functionalities of the General Purpose Input/Output (EXTI) peripheral:
  *           + Initialization and de-initialization functions
  *           + IO operation functions
  *
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2019 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  @verbatim
  ==============================================================================
                    ##### EXTI Peripheral features #####
  ==============================================================================
  [..]
    (+) Each Exti line can be configured within this driver.

    (+) Exti line can be configured in 3 different modes
        (++) Interrupt
        (++) Event
        (++) Both of them

    (+) Configurable Exti lines can be configured with 3 different triggers
        (++) Rising
        (++) Falling
        (++) Both of them

    (+) When set in interrupt mode, configurable Exti lines have two different
        interrupt pending registers which allow to distinguish which transition
        occurs:
        (++) Rising edge pending interrupt
        (++) Falling

    (+) Exti lines 0 to 15 are linked to gpio pin number 0 to 15. Gpio port can
        be selected through multiplexer.

                     ##### How to use this driver #####
  ==============================================================================
  [..]

    (#) Configure the EXTI line using HAL_EXTI_SetConfigLine().
        (++) Choose the interrupt line number by setting "Line" member from
             EXTI_ConfigTypeDef structure.
        (++) Configure the interrupt and/or event mode using "Mode" member from
             EXTI_ConfigTypeDef structure.
        (++) For configurable lines, configure rising and/or falling trigger
             "Trigger" member from EXTI_ConfigTypeDef structure.
        (++) For Exti lines linked to gpio, choose gpio port using "GPIOSel"
             member from GPIO_InitTypeDef structure.

    (#) Get current Exti configuration of a dedicated line using
        HAL_EXTI_GetConfigLine().
        (++) Provide exiting handle as parameter.
        (++) Provide pointer on EXTI_ConfigTypeDef structure as second parameter.

    (#) Clear Exti configuration of a dedicated line using HAL_EXTI_GetConfigLine().
        (++) Provide exiting handle as parameter.

    (#) Register callback to treat Exti interrupts using HAL_EXTI_RegisterCallback().
        (++) Provide exiting handle as first parameter.
        (++) Provide which callback will be registered using one value from
             EXTI_CallbackIDTypeDef.
        (++) Provide callback function pointer.

    (#) Get interrupt pending bit using HAL_EXTI_GetPending().

    (#) Clear interrupt pending bit using HAL_EXTI_ClearPending().

    (#) Generate software interrupt using HAL_EXTI_GenerateSWI().

  @endverbatim
  */

/* Includes ------------------------------------------------------------------*/
#include "stm32g4xx_hal.h"

/** @addtogroup STM32G4xx_HAL_Driver
  * @{
  */

/** @addtogroup EXTI
  * @{
  */
/** MISRA C:2012 deviation rule has been granted for following rule:
  * Rule-18.1_b - Medium: Array `EXTICR' 1st subscript interval [0,7] may be out
  * of bounds [0,3] in following API :
  * HAL_EXTI_SetConfigLine
  * HAL_EXTI_GetConfigLine
  * HAL_EXTI_ClearConfigLine
  */

#ifdef HAL_EXTI_MODULE_ENABLED

/* Private typedef -----------------------------------------------------------*/
/* Private defines ------------------------------------------------------------*/
/** @defgroup EXTI_Private_Constants EXTI Private Constants
  * @{
  */
#define EXTI_MODE_OFFSET                    0x08U   /* 0x20: offset between MCU IMR/EMR registers */
#define EXTI_CONFIG_OFFSET                  0x08U   /* 0x20: offset between MCU Rising/Falling configuration registers */
/**
  * @}
  */

/* Private macros ------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Exported functions --------------------------------------------------------*/

/** @addtogroup EXTI_Exported_Functions
  * @{
  */

/** @addtogroup EXTI_Exported_Functions_Group1
  *  @brief    Configuration functions
  *
@verbatim
 ===============================================================================
              ##### Configuration functions #####
 ===============================================================================

@endverbatim
  * @{
  */

/**
  * @brief  Set configuration of a dedicated Exti line.
  * @param  hexti Exti handle.
  * @param  pExtiConfig Pointer on EXTI configuration to be set.
  * @retval HAL Status.
  */
HAL_StatusTypeDef HAL_EXTI_SetConfigLine(EXTI_HandleTypeDef *hexti, EXTI_ConfigTypeDef *pExtiConfig)
{
    __IO uint32_t *regaddr;
    uint32_t regval;
    uint32_t linepos;
    uint32_t maskline;
    uint32_t offset;

    /* Check null pointer */
    if ((hexti == NULL) || (pExtiConfig == NULL))
    {
        return HAL_ERROR;
    }

    /* Check parameters */
    assert_param(IS_EXTI_LINE(pExtiConfig->Line));
    assert_param(IS_EXTI_MODE(pExtiConfig->Mode));

    /* Assign line number to handle */
    hexti->Line = pExtiConfig->Line;

    /* Compute line register offset */
    offset = ((pExtiConfig->Line & EXTI_REG_MASK) >> EXTI_REG_SHIFT);
    /* Compute line position */
    linepos = (pExtiConfig->Line & EXTI_PIN_MASK);
    /* Compute line mask */
    maskline = (1uL << linepos);

    /* Configure triggers for configurable lines */
    if ((pExtiConfig->Line & EXTI_CONFIG) != 0x00u)
    {
        assert_param(IS_EXTI_TRIGGER(pExtiConfig->Trigger));

        /* Configure rising trigger */
        regaddr = (&EXTI->RTSR1 + (EXTI_CONFIG_OFFSET * offset));
        regval = *regaddr;

        /* Mask or set line */
        if ((pExtiConfig->Trigger & EXTI_TRIGGER_RISING) != 0x00u)
        {
            regval |= maskline;
        }
        else
        {
            regval &= ~maskline;
        }

        /* Store rising trigger mode */
        *regaddr = regval;

        /* Configure falling trigger */
        regaddr = (&EXTI->FTSR1 + (EXTI_CONFIG_OFFSET * offset));
        regval = *regaddr;

        /* Mask or set line */
        if ((pExtiConfig->Trigger & EXTI_TRIGGER_FALLING) != 0x00u)
        {
            regval |= maskline;
        }
        else
        {
            regval &= ~maskline;
        }

        /* Store falling trigger mode */
        *regaddr = regval;

        /* Configure gpio port selection in case of gpio exti line */
        if ((pExtiConfig->Line & EXTI_GPIO) == EXTI_GPIO)
        {
            assert_param(IS_EXTI_GPIO_PORT(pExtiConfig->GPIOSel));
            assert_param(IS_EXTI_GPIO_PIN(linepos));

            regval = SYSCFG->EXTICR[linepos >> 2u];
            regval &= ~(SYSCFG_EXTICR1_EXTI0 << (SYSCFG_EXTICR1_EXTI1_Pos * (linepos & 0x03u)));
            regval |= (pExtiConfig->GPIOSel << (SYSCFG_EXTICR1_EXTI1_Pos * (linepos & 0x03u)));
            SYSCFG->EXTICR[linepos >> 2u] = regval;
        }
    }

    /* Configure interrupt mode : read current mode */
    regaddr = (&EXTI->IMR1 + (EXTI_MODE_OFFSET * offset));
    regval = *regaddr;

    /* Mask or set line */
    if ((pExtiConfig->Mode & EXTI_MODE_INTERRUPT) != 0x00u)
    {
        regval |= maskline;
    }
    else
    {
        regval &= ~maskline;
    }

    /* Store interrupt mode */
    *regaddr = regval;

    /* Configure event mode : read current mode */
    regaddr = (&EXTI->EMR1 + (EXTI_MODE_OFFSET * offset));
    regval = *regaddr;

    /* Mask or set line */
    if ((pExtiConfig->Mode & EXTI_MODE_EVENT) != 0x00u)
    {
        regval |= maskline;
    }
    else
    {
        regval &= ~maskline;
    }

    /* Store event mode */
    *regaddr = regval;

    return HAL_OK;
}


/**
  * @brief  Get configuration of a dedicated Exti line.
  * @param  hexti Exti handle.
  * @param  pExtiConfig Pointer on structure to store Exti configuration.
  * @retval HAL Status.
  */
HAL_StatusTypeDef HAL_EXTI_GetConfigLine(EXTI_HandleTypeDef *hexti, EXTI_ConfigTypeDef *pExtiConfig)
{
    __IO uint32_t *regaddr;
    uint32_t regval;
    uint32_t linepos;
    uint32_t maskline;
    uint32_t offset;

    /* Check null pointer */
    if ((hexti == NULL) || (pExtiConfig == NULL))
    {
        return HAL_ERROR;
    }

    /* Check the parameter */
    assert_param(IS_EXTI_LINE(hexti->Line));

    /* Store handle line number to configuration structure */
    pExtiConfig->Line = hexti->Line;

    /* Compute line register offset and line mask */
    offset = ((pExtiConfig->Line & EXTI_REG_MASK) >> EXTI_REG_SHIFT);
    /* Compute line position */
    linepos = (pExtiConfig->Line & EXTI_PIN_MASK);
    /* Compute mask */
    maskline = (1uL << linepos);

    /* 1] Get core mode : interrupt */
    regaddr = (&EXTI->IMR1 + (EXTI_MODE_OFFSET * offset));
    regval = *regaddr;

    /* Check if selected line is enable */
    if ((regval & maskline) != 0x00u)
    {
        pExtiConfig->Mode = EXTI_MODE_INTERRUPT;
    }
    else
    {
        pExtiConfig->Mode = EXTI_MODE_NONE;
    }

    /* Get event mode */
    regaddr = (&EXTI->EMR1 + (EXTI_MODE_OFFSET * offset));
    regval = *regaddr;

    /* Check if selected line is enable */
    if ((regval & maskline) != 0x00u)
    {
        pExtiConfig->Mode |= EXTI_MODE_EVENT;
    }

    /* Get default Trigger and GPIOSel configuration */
    pExtiConfig->Trigger = EXTI_TRIGGER_NONE;
    pExtiConfig->GPIOSel = 0x00u;

    /* 2] Get trigger for configurable lines : rising */
    if ((pExtiConfig->Line & EXTI_CONFIG) != 0x00u)
    {
        regaddr = (&EXTI->RTSR1 + (EXTI_CONFIG_OFFSET * offset));
        regval = *regaddr;

        /* Check if configuration of selected line is enable */
        if ((regval & maskline) != 0x00u)
        {
            pExtiConfig->Trigger = EXTI_TRIGGER_RISING;
        }

        /* Get falling configuration */
        regaddr = (&EXTI->FTSR1 + (EXTI_CONFIG_OFFSET * offset));
        regval = *regaddr;

        /* Check if configuration of selected line is enable */
        if ((regval & maskline) != 0x00u)
        {
            pExtiConfig->Trigger |= EXTI_TRIGGER_FALLING;
        }

        /* Get Gpio port selection for gpio lines */
        if ((pExtiConfig->Line & EXTI_GPIO) == EXTI_GPIO)
        {
            assert_param(IS_EXTI_GPIO_PIN(linepos));

            regval = SYSCFG->EXTICR[linepos >> 2u];
            pExtiConfig->GPIOSel = ((regval >> (SYSCFG_EXTICR1_EXTI1_Pos * ((linepos & 0x03u)))));
        }
    }

    return HAL_OK;
}


/**
  * @brief  Clear whole configuration of a dedicated Exti line.
  * @param  hexti Exti handle.
  * @retval HAL Status.
  */
HAL_StatusTypeDef HAL_EXTI_ClearConfigLine(EXTI_HandleTypeDef *hexti)
{
    __IO uint32_t *regaddr;
    uint32_t regval;
    uint32_t linepos;
    uint32_t maskline;
    uint32_t offset;

    /* Check null pointer */
    if (hexti == NULL)
    {
        return HAL_ERROR;
    }

    /* Check the parameter */
    assert_param(IS_EXTI_LINE(hexti->Line));

    /* compute line register offset and line mask */
    offset = ((hexti->Line & EXTI_REG_MASK) >> EXTI_REG_SHIFT);
    /* compute line position */
    linepos = (hexti->Line & EXTI_PIN_MASK);
    /* compute line mask */
    maskline = (1uL << linepos);

    /* 1] Clear interrupt mode */
    regaddr = (&EXTI->IMR1 + (EXTI_MODE_OFFSET * offset));
    regval = (*regaddr & ~maskline);
    *regaddr = regval;

    /* 2] Clear event mode */
    regaddr = (&EXTI->EMR1 + (EXTI_MODE_OFFSET * offset));
    regval = (*regaddr & ~maskline);
    *regaddr = regval;

    /* 3] Clear triggers in case of configurable lines */
    if ((hexti->Line & EXTI_CONFIG) != 0x00u)
    {
        regaddr = (&EXTI->RTSR1 + (EXTI_CONFIG_OFFSET * offset));
        regval = (*regaddr & ~maskline);
        *regaddr = regval;

        regaddr = (&EXTI->FTSR1 + (EXTI_CONFIG_OFFSET * offset));
        regval = (*regaddr & ~maskline);
        *regaddr = regval;

        /* Get Gpio port selection for gpio lines */
        if ((hexti->Line & EXTI_GPIO) == EXTI_GPIO)
        {
            assert_param(IS_EXTI_GPIO_PIN(linepos));

            regval = SYSCFG->EXTICR[linepos >> 2u];
            regval &= ~(SYSCFG_EXTICR1_EXTI0 << (SYSCFG_EXTICR1_EXTI1_Pos * (linepos & 0x03u)));
            SYSCFG->EXTICR[linepos >> 2u] = regval;
        }
    }

    return HAL_OK;
}


/**
  * @brief  Register callback for a dedicated Exti line.
  * @param  hexti Exti handle.
  * @param  CallbackID User callback identifier.
  *         This parameter can be one of @arg @ref EXTI_CallbackIDTypeDef values.
  * @param  pPendingCbfn function pointer to be stored as callback.
  * @retval HAL Status.
  */
HAL_StatusTypeDef HAL_EXTI_RegisterCallback(EXTI_HandleTypeDef *hexti, EXTI_CallbackIDTypeDef CallbackID, void (*pPendingCbfn)(void))
{
    HAL_StatusTypeDef status = HAL_OK;

    /* Check the parameters */
    assert_param(IS_EXTI_CB(CallbackID));

    switch (CallbackID)
    {
    /* set common callback */
    case  HAL_EXTI_COMMON_CB_ID:
        hexti->PendingCallback = pPendingCbfn;
        break;

    default:
        hexti->PendingCallback = NULL;
        status = HAL_ERROR;
        break;
    }

    return status;
}


/**
  * @brief  Store line number as handle private field.
  * @param  hexti Exti handle.
  * @param  ExtiLine Exti line number.
  *         This parameter can be from 0 to @ref EXTI_LINE_NB.
  * @retval HAL Status.
  */
HAL_StatusTypeDef HAL_EXTI_GetHandle(EXTI_HandleTypeDef *hexti, uint32_t ExtiLine)
{
    /* Check the parameters */
    assert_param(IS_EXTI_LINE(ExtiLine));

    /* Check null pointer */
    if (hexti == NULL)
    {
        return HAL_ERROR;
    }
    else
    {
        /* Store line number as handle private field */
        hexti->Line = ExtiLine;

        return HAL_OK;
    }
}


/**
  * @}
  */

/** @addtogroup EXTI_Exported_Functions_Group2
  *  @brief EXTI IO functions.
  *
@verbatim
 ===============================================================================
                       ##### IO operation functions #####
 ===============================================================================

@endverbatim
  * @{
  */

/**
  * @brief  Handle EXTI interrupt request.
  * @param  hexti Exti handle.
  * @retval none.
  */
void HAL_EXTI_IRQHandler(EXTI_HandleTypeDef *hexti)
{
    __IO uint32_t *regaddr;
    uint32_t regval;
    uint32_t maskline;
    uint32_t offset;

    /* Compute line register offset */
    offset = ((hexti->Line & EXTI_REG_MASK) >> EXTI_REG_SHIFT);
    /* compute line mask */
    maskline = (1uL << (hexti->Line & EXTI_PIN_MASK));

    /* Get pending bit  */
    regaddr = (&EXTI->PR1 + (EXTI_CONFIG_OFFSET * offset));
    regval = (*regaddr & maskline);

    if (regval != 0x00u)
    {
        /* Clear pending bit */
        *regaddr = maskline;

        /* Call pending callback */
        if (hexti->PendingCallback != NULL)
        {
            hexti->PendingCallback();
        }
    }
}

/**
  * @brief  Get interrupt pending bit of a dedicated line.
  * @param  hexti Exti handle.
  * @param  Edge unused
  * @retval 1 if interrupt is pending else 0.
  */
uint32_t HAL_EXTI_GetPending(EXTI_HandleTypeDef *hexti, uint32_t Edge)
{
    __IO uint32_t *regaddr;
    uint32_t regval;
    uint32_t linepos;
    uint32_t maskline;
    uint32_t offset;

    /* Check parameters */
    assert_param(IS_EXTI_LINE(hexti->Line));
    assert_param(IS_EXTI_CONFIG_LINE(hexti->Line));
    UNUSED(Edge);

    /* Compute line register offset */
    offset = ((hexti->Line & EXTI_REG_MASK) >> EXTI_REG_SHIFT);
    /* Compute line position */
    linepos = (hexti->Line & EXTI_PIN_MASK);
    /* Compute line mask */
    maskline = (1uL << linepos);

    /* Get pending bit */
    regaddr = (&EXTI->PR1 + (EXTI_CONFIG_OFFSET * offset));

    /* return 1 if bit is set else 0 */
    regval = ((*regaddr & maskline) >> linepos);
    return regval;
}


/**
  * @brief  Clear interrupt pending bit of a dedicated line.
  * @param  hexti Exti handle.
  * @param  Edge unused
  * @retval None.
  */
void HAL_EXTI_ClearPending(EXTI_HandleTypeDef *hexti, uint32_t Edge)
{
    __IO uint32_t *regaddr;
    uint32_t maskline;
    uint32_t offset;

    /* Check parameters */
    assert_param(IS_EXTI_LINE(hexti->Line));
    assert_param(IS_EXTI_CONFIG_LINE(hexti->Line));
    UNUSED(Edge);

    /* Compute line register offset */
    offset = ((hexti->Line & EXTI_REG_MASK) >> EXTI_REG_SHIFT);
    /* Compute line mask */
    maskline = (1uL << (hexti->Line & EXTI_PIN_MASK));

    /* Get pending register address */
    regaddr = (&EXTI->PR1 + (EXTI_CONFIG_OFFSET * offset));

    /* Clear Pending bit */
    *regaddr =  maskline;
}


/**
  * @brief  Generate a software interrupt for a dedicated line.
  * @param  hexti Exti handle.
  * @retval None.
  */
void HAL_EXTI_GenerateSWI(EXTI_HandleTypeDef *hexti)
{
    __IO uint32_t *regaddr;
    uint32_t maskline;
    uint32_t offset;

    /* Check parameter */
    assert_param(IS_EXTI_LINE(hexti->Line));
    assert_param(IS_EXTI_CONFIG_LINE(hexti->Line));

    /* compute line register offset */
    offset = ((hexti->Line & EXTI_REG_MASK) >> EXTI_REG_SHIFT);
    /* compute line mask */
    maskline = (1uL << (hexti->Line & EXTI_PIN_MASK));

    regaddr = (&EXTI->SWIER1 + (EXTI_CONFIG_OFFSET * offset));
    *regaddr = maskline;
}


/**
  * @}
  */

/**
  * @}
  */

#endif /* HAL_EXTI_MODULE_ENABLED */
/**
  * @}
  */

/**
  * @}
  */

